Bug 347117 - [Help] Enhancement in Web API for About and Nav servicesv20110725

13 files changed, 662 insertions, 47 deletions

diff --git a/org.eclipse.help.webapp/plugin.xml b/org.eclipse.help.webapp/plugin.xml
index 187f3c94e..c511da422 100644
--- a/org.eclipse.help.webapp/plugin.xml
+++ b/org.eclipse.help.webapp/plugin.xml
@@ -238,6 +238,10 @@
             class="org.eclipse.help.internal.webapp.service.ExtensionService">
       </servlet>
       <servlet
+            alias="/service/about"
+            class="org.eclipse.help.internal.webapp.service.AboutService">
+      </servlet>
+      <servlet
             alias="/service/about.html"
             class="org.eclipse.help.internal.webapp.service.AboutService">
       </servlet>
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/AboutParser.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/AboutParser.java
new file mode 100644
index 000000000..766b422ee
--- /dev/null
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/AboutParser.java
@@ -0,0 +1,121 @@
+/*******************************************************************************
+ * Copyright (c) 2011 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.help.internal.webapp.parser;
+
+import java.util.Properties;
+
+import org.eclipse.help.internal.webapp.utils.JSonHelper;
+import org.eclipse.help.internal.webapp.utils.Utils;
+import org.eclipse.help.internal.webapp.utils.XMLHelper;
+import org.xml.sax.Attributes;
+
+public class AboutParser extends ResultParser {
+
+	private ParseElement element = null;
+	private String currentTag;
+	private long service;
+
+	public AboutParser(long service) {
+		super(JSonHelper.TITLE);
+		this.service = service;
+		if (this.service == Utils.ABOUT_PLUGIN)
+			this.setIdentifier(JSonHelper.PLUGIN_ID);
+	}
+	
+	public void startElement(String uri, String lname, String name, Attributes attrs) {
+		
+		currentTag = name;
+		
+		Properties properties = new Properties();
+		properties.put(JSonHelper.PROPERTY_NAME, name);
+		if (!((service == Utils.PREFERENCE 
+					&& (name.equalsIgnoreCase(XMLHelper.ELEMENT_PREFERENCES) 
+							|| name.equalsIgnoreCase(XMLHelper.ELEMENT_PLUGIN))) 
+				|| service == Utils.ABOUT_PLUGIN))
+			properties.put(JSonHelper.PROPERTY_VALUE, ""); //$NON-NLS-1$
+		
+		for (int i = 0; i < attrs.getLength(); i++) {
+			String qname = attrs.getQName(i);
+			String val = attrs.getValue(i);
+			properties.put(qname, val);
+		}
+		
+		ParseElement elem = new ParseElement(properties, element);
+		if (element != null)
+			element.addChild(elem);
+		else
+			items.add(elem);
+		
+		element = elem;
+	}
+	
+	public void characters(char[] ch, int start, int length) {
+		if ((service == Utils.PREFERENCE 
+				&& (currentTag.equalsIgnoreCase(XMLHelper.ELEMENT_PREFERENCES) 
+					|| currentTag.equalsIgnoreCase(XMLHelper.ELEMENT_PLUGIN))) 
+			|| service == Utils.ABOUT_PLUGIN)
+			return;
+			
+		if (element != null && !currentTag.equals("")) { //$NON-NLS-1$
+			
+			Properties properties = element.getProps();
+			if (properties != null) {
+				
+				String content = new String(ch, start, length);
+				
+				String existing = (String) properties.get(currentTag);
+				if (existing == null)
+					existing = ""; //$NON-NLS-1$
+				
+				content = content.replaceAll("[\\n\\t]", "").trim(); //$NON-NLS-1$ //$NON-NLS-2$
+				
+				properties.put(JSonHelper.PROPERTY_VALUE, existing + content);
+				element.updateParseElement(properties);
+			}
+		}
+	}
+	
+	public void endElement(String uri, String lname, String name) {
+		
+		if (element != null) {
+			element = element.getParent();
+		}
+		currentTag = ""; //$NON-NLS-1$
+	}
+	
+	public String toJSON() {
+		
+		StringBuffer buf = new StringBuffer();
+		
+		buf.append(JSonHelper.BEGIN_BRACE);
+		buf.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+		
+		buf.append(JSonHelper.IDENTIFIER);
+		buf.append(JSonHelper.COLON);
+		buf.append(JSonHelper.getQuotes(id));
+		buf.append(JSonHelper.COMMA);
+
+		buf.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+		buf.append(JSonHelper.LABEL);
+		buf.append(JSonHelper.COLON);
+		buf.append(JSonHelper.getQuotes(label));
+		buf.append(JSonHelper.COMMA);
+		
+		ParseElement elem = (ParseElement) items.get(0);
+		if (elem != null)
+			buf.append(elem.toJSON());
+		
+		buf.append(JSonHelper.END_BRACE);
+		
+		return buf.toString();
+	}
+
+}
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/NavParser.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/NavParser.java
new file mode 100644
index 000000000..4dc2e38cb
--- /dev/null
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/NavParser.java
@@ -0,0 +1,80 @@
+/*******************************************************************************
+ * Copyright (c) 2011 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.help.internal.webapp.parser;
+
+import java.util.Properties;
+
+import org.eclipse.help.internal.webapp.utils.JSonHelper;
+import org.xml.sax.Attributes;
+
+public class NavParser extends ResultParser {
+
+	private ParseElement element = null;
+
+	public NavParser() {
+		super(JSonHelper.TITLE);
+	}
+	
+	public void startElement(String uri, String lname, String name, Attributes attrs) {
+		
+		Properties properties = new Properties();
+		properties.put(JSonHelper.PROPERTY_NAME, name);
+		
+		for (int i = 0; i < attrs.getLength(); i++) {
+			String qname = attrs.getQName(i);
+			String val = attrs.getValue(i);
+			properties.put(qname, val);
+		}
+		
+		ParseElement elem = new ParseElement(properties, element);
+		if (element != null)
+			element.addChild(elem);
+		else
+			items.add(elem);
+		
+		element = elem;
+	}
+	
+	public void endElement(String uri, String lname, String name) {
+		
+		if (element != null) {
+			element = element.getParent();
+		}
+	}
+	
+	public String toJSON() {
+		
+		StringBuffer buf = new StringBuffer();
+		
+		buf.append(JSonHelper.BEGIN_BRACE);
+		buf.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+		
+		buf.append(JSonHelper.IDENTIFIER);
+		buf.append(JSonHelper.COLON);
+		buf.append(JSonHelper.getQuotes(id));
+		buf.append(JSonHelper.COMMA);
+
+		buf.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+		buf.append(JSonHelper.LABEL);
+		buf.append(JSonHelper.COLON);
+		buf.append(JSonHelper.getQuotes(label));
+		buf.append(JSonHelper.COMMA);
+		
+		ParseElement elem = (ParseElement) items.get(0);
+		if (elem != null)
+			buf.append(elem.toJSON());
+		
+		buf.append(JSonHelper.END_BRACE);
+		
+		return buf.toString();
+	}
+
+}
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ParseElement.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ParseElement.java
index 152b714a4..e22f72a60 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ParseElement.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ParseElement.java
@@ -127,4 +127,61 @@ public class ParseElement {
 		
 		return buff.toString();
 	}
+	
+	public String toJSON() {
+		
+		StringBuffer buff = new StringBuffer();
+		
+		if (props != null) {
+			Enumeration enumObj = props.keys();
+			while (enumObj.hasMoreElements()) {
+				
+				String key = (String) enumObj.nextElement();
+				String val = props.getProperty(key);
+				
+				buff.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+				buff.append(key);
+				buff.append(JSonHelper.COLON);
+				try {
+					val = URLEncoder.encode(val, "UTF-8"); //$NON-NLS-1$
+				} catch (UnsupportedEncodingException e) {
+					e.printStackTrace();
+				}
+				buff.append(JSonHelper.getQuotes(val));
+				buff.append(JSonHelper.COMMA);
+			}
+		}
+		
+		if (children.size() <= 0) {
+			int len = buff.length();
+			char ch = buff.charAt(len - 1);
+			if (ch == ',') {
+				buff.deleteCharAt(len - 1);
+				buff.append(JSonHelper.NEWLINE);
+			}
+			
+		} else {
+			
+			buff.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+			buff.append(JSonHelper.ITEMS);
+			buff.append(JSonHelper.COLON);
+			buff.append(JSonHelper.BEGIN_BRACKET);
+			
+			for (int i = 0; i < children.size(); i++) {
+				
+				if (i > 0)
+					buff.append(JSonHelper.COMMA);
+				
+				ParseElement child = (ParseElement) children.get(i);
+				buff.append(child.toJSON(1));
+			}
+			
+			buff.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
+			
+			buff.append(JSonHelper.END_BRACKET);
+			buff.append(JSonHelper.NEWLINE);
+		}
+		
+		return buff.toString();
+	}
 }
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ResultParser.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ResultParser.java
index 08c7e866e..c078a14b6 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ResultParser.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/parser/ResultParser.java
@@ -25,17 +25,23 @@ import org.xml.sax.helpers.DefaultHandler;
 
 public class ResultParser extends DefaultHandler {
 
-	private String label = ""; //$NON-NLS-1$
+	protected String id;
+	protected String label;
 	protected ArrayList items = new ArrayList(); //parser populates the items arrayList withe parsed data.
 
 	public ResultParser(String label) {
+		this(label, JSonHelper.ID);
+	}
+	
+	public ResultParser(String label, String id) {
 		this.label = label;
+		this.id = id;
 	}
 	
-	public void parse(URL tocURL) 
+	public void parse(URL url) 
 		throws ParserConfigurationException, SAXException, IOException
 	{
-		parse(tocURL.openStream());
+		parse(url.openStream());
 	}
 	
 	public void parse(InputStream in) 
@@ -49,6 +55,10 @@ public class ResultParser extends DefaultHandler {
 		this.label = label;
 	}
 	
+	public void setIdentifier(String id) {
+		this.id = id;
+	}
+	
 	public ArrayList getItems()
 	{
 		return items;
@@ -68,7 +78,7 @@ public class ResultParser extends DefaultHandler {
 		
 		buf.append(JSonHelper.IDENTIFIER);
 		buf.append(JSonHelper.COLON);
-		buf.append(JSonHelper.getQuotes(JSonHelper.ID));
+		buf.append(JSonHelper.getQuotes(id));
 		buf.append(JSonHelper.COMMA);
 
 		buf.append(JSonHelper.NEWLINE + JSonHelper.SPACE);
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/AboutService.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/AboutService.java
index 7365b1c80..45a302358 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/AboutService.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/AboutService.java
@@ -10,12 +10,33 @@
  *******************************************************************************/
 package org.eclipse.help.internal.webapp.service;
 
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.List;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.eclipse.help.internal.webapp.HelpWebappPlugin;
+import org.eclipse.help.internal.webapp.WebappResources;
+import org.eclipse.help.internal.webapp.data.UrlUtil;
+import org.eclipse.help.internal.webapp.parser.AboutParser;
 import org.eclipse.help.internal.webapp.servlet.AboutServlet;
+import org.eclipse.help.internal.webapp.servlet.PreferenceWriter;
+import org.eclipse.help.internal.webapp.servlet.XMLGenerator;
+import org.eclipse.help.internal.webapp.utils.Utils;
+import org.osgi.framework.Bundle;
 
 /**
- * Generates an html page having informations about either <code>User-Agent</code>,
- * Help system <code>preferences</code> or the available plug-ins in Help system
- * like Provider, Plugin name, Version and PluginId.
+ * Generates either xml, json or html page having informations about either 
+ * <code>User-Agent</code>, Help system <code>preferences</code> or the available 
+ * plug-ins in Help system like Provider, Plugin name, Version and PluginId.
  * 
  * <p>Extends the {@link org.eclipse.help.internal.webapp.servlet.AboutServlet}
  * servlet.
@@ -25,12 +46,17 @@ import org.eclipse.help.internal.webapp.servlet.AboutServlet;
  * 						<code>preferences</code> to view the Help system preferences.
  * 						Do not specify any value to show the available plugins in
  * 						Help web application.
- * @param sortColumn	- (Optional) specifying the column number over
- * 						which displayed output needs to be sorted. Applicable only if
- * 						<code>show</code> parameter is <code>null</code>. 
+ * @param sortColumn	- (Optional) specifying the column number of the available 
+ * 						plug-ins in Help system over which displayed output needs 
+ * 						to be sorted. Applicable only if <code>show</code> parameter 
+ * 						is <code>null</code>.
+ * @param returnType	- (Optional) specifies the return type of the servlet.
+ * 						  Accepts either <code>xml</code> (default) or <code>html</code>
+ * 						  or <code>json</code>
  * 
- * @return		Html page having informations about either <code>User-Agent</code>,
- * <code>preferences</code> or the available plug-ins.
+ * @return		Informations about either <code>User-Agent</code>, <code>preferences</code>
+ * 				or the available plug-ins, either as <code>xml</code> (default) or
+ * 				<code>html</code> or <code>json</code>
  * 
  * @version	$Version$
  * 
@@ -38,5 +64,166 @@ import org.eclipse.help.internal.webapp.servlet.AboutServlet;
 public class AboutService extends AboutServlet {
 
 	private static final long serialVersionUID = 1L;
+	
+	private long service;
+
+	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
+			throws ServletException, IOException {
+		
+		req.setCharacterEncoding("UTF-8"); //$NON-NLS-1$
+		
+		String returnType = req.getParameter(Utils.RETURN_TYPE);
+		boolean boolIsHTML = (returnType != null 
+				&& returnType.equalsIgnoreCase(Utils.HTML));
+		// If HTML output is required, call AboutServlet class
+		if (boolIsHTML) {
+			super.doGet(req, resp);
+			return;
+		}
+		
+		// Set standard HTTP/1.1 no-cache headers.
+		resp.setHeader("Cache-Control",  //$NON-NLS-1$
+				"no-store, no-cache, must-revalidate"); //$NON-NLS-1$
+		resp.setContentType("application/xml; charset=UTF-8"); //$NON-NLS-1$
+		locale = UrlUtil.getLocaleObj(req, resp);
+		
+		// create XML response
+		String response = processRequest(req, resp);
+		
+		boolean boolIsJSON = (returnType != null 
+				&& returnType.equalsIgnoreCase(Utils.JSON));
+		
+		// If JSON output is required
+		if (boolIsJSON) {
+			resp.setContentType("text/plain"); //$NON-NLS-1$
+			response = getJSONResponse(response);
+		}
+		
+		resp.getWriter().write(response);
+	}
+
+	protected String getJSONResponse(String response)
+			throws IOException {
+		AboutParser aboutParser = new AboutParser(service);
+		InputStream is = null;
+		try {
+			if (response != null) {
+				is = new ByteArrayInputStream(response.getBytes("UTF-8")); //$NON-NLS-1$
+				aboutParser.parse(is);
+			}
+
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		
+		if (is != null)
+			is.close();
+
+		// Call after the catch.
+		// An empty JSON is created if any Exception is thrown
+		// Else returns the complete JSON
+		return aboutParser.toJSON();
+	}
+
+	private String processRequest(HttpServletRequest req, HttpServletResponse resp)
+			throws ServletException, IOException {
+		StringBuffer buf = new StringBuffer();
+		buf.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"); //$NON-NLS-1$
+		
+		String showParam = req.getParameter("show"); //$NON-NLS-1$
+		if ("agent".equalsIgnoreCase(showParam)) { //$NON-NLS-1$
+			getAgent(buf, req, resp);
+		} else if ("preferences".equalsIgnoreCase(showParam)) { //$NON-NLS-1$
+			getPreferences(buf, resp);
+		} else {
+			getAboutPlugins(buf, req, resp);
+		}
+		
+		return buf.toString();
+	}
+
+	private void getAgent(StringBuffer buf, HttpServletRequest req, HttpServletResponse resp)
+			throws IOException {
+		service = Utils.AGENT;
+		
+		String title = WebappResources.getString("userAgent", locale); //$NON-NLS-1$
+		String agent = req.getHeader("User-Agent"); //$NON-NLS-1$
+		buf.append("<userAgent\n      title=\""); //$NON-NLS-1$
+		buf.append(XMLGenerator.xmlEscape(title));
+		buf.append("\">"); //$NON-NLS-1$
+		buf.append(agent);
+		buf.append("</userAgent>"); //$NON-NLS-1$
+	}
+
+	private void getPreferences(StringBuffer buf, HttpServletResponse resp)
+			throws IOException {
+		service = Utils.PREFERENCE;
+		
+		String title = WebappResources.getString("preferences", locale); //$NON-NLS-1$
+		buf.append("<preferences\n      title=\""); //$NON-NLS-1$
+		buf.append(XMLGenerator.xmlEscape(title));
+		buf.append("\">"); //$NON-NLS-1$
+		PreferenceWriter writer = new PreferenceWriter(buf, locale, true);
+		writer.writePreferences();
+		buf.append("\n</preferences>"); //$NON-NLS-1$
+	}
+
+	private void getAboutPlugins(StringBuffer buf, HttpServletRequest req, HttpServletResponse resp)
+			throws IOException {
+		service = Utils.ABOUT_PLUGIN;
+		
+		String sortParam = req.getParameter("sortColumn"); //$NON-NLS-1$
+		int sortColumn = 3;
+		if (sortParam != null) {
+			try {
+				sortColumn = Integer.parseInt(sortParam);
+			} catch (NumberFormatException e) {}	
+		}
+		
+		String title = WebappResources.getString("aboutPlugins", locale); //$NON-NLS-1$
+		buf.append("<aboutPlugins\n      title=\""); //$NON-NLS-1$
+		buf.append(XMLGenerator.xmlEscape(title));
+		buf.append("\""); //$NON-NLS-1$
+		
+		List plugins = new ArrayList();
+		
+		Bundle[] bundles = HelpWebappPlugin.getContext().getBundles();
+		for (int k = 0; k < bundles.length; k++) {
+         	plugins.add(pluginDetails(bundles[k]));
+        }
+		
+        Comparator pluginComparator = new PluginComparator(sortColumn);
+		Collections.sort(plugins, pluginComparator );
+		
+		String[] headerColumns = new String[]{
+		    "provider", //$NON-NLS-1$
+		    "pluginName", //$NON-NLS-1$
+		    "version", //$NON-NLS-1$
+		    "pluginId" //$NON-NLS-1$
+		};
+		
+		for (int i = 0; i < headerColumns.length; i++) {
+			buf.append("\n          "); //$NON-NLS-1$
+			buf.append(headerColumns[i]);
+			buf.append("=\""); //$NON-NLS-1$
+			buf.append(XMLGenerator.xmlEscape(WebappResources.getString(headerColumns[i], locale)));
+			buf.append("\""); //$NON-NLS-1$
+		}
+		buf.append(">"); //$NON-NLS-1$
+		
+		for (Iterator iter = plugins.iterator(); iter.hasNext();) {
+			PluginDetails details = (PluginDetails) iter.next();
+			buf.append("\n        <plugin"); //$NON-NLS-1$
+			for (int i = 0; i < headerColumns.length; i++) {
+				buf.append("\n          "); //$NON-NLS-1$
+				buf.append(headerColumns[i]);
+				buf.append("=\""); //$NON-NLS-1$
+				buf.append(XMLGenerator.xmlEscape(details.columns[i]));
+				buf.append("\""); //$NON-NLS-1$
+			}
+			buf.append(">\n        </plugin>"); //$NON-NLS-1$
+		}
+		buf.append("\n</aboutPlugins>"); //$NON-NLS-1$
+	}
 
 }
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/NavService.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/NavService.java
index a6ac5eb46..987b2392f 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/NavService.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/service/NavService.java
@@ -10,23 +10,33 @@
  *******************************************************************************/
 package org.eclipse.help.internal.webapp.service;
 
+import java.io.ByteArrayInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.net.URL;
+import java.util.Locale;
 
 import javax.servlet.ServletException;
-import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.eclipse.help.ITopic;
+import org.eclipse.help.base.AbstractHelpScope;
+import org.eclipse.help.internal.base.scope.ScopeUtils;
+import org.eclipse.help.internal.webapp.data.RequestScope;
+import org.eclipse.help.internal.webapp.data.UrlUtil;
+import org.eclipse.help.internal.webapp.parser.NavParser;
+import org.eclipse.help.internal.webapp.servlet.NavServlet;
+import org.eclipse.help.internal.webapp.servlet.XMLGenerator;
 import org.eclipse.help.internal.webapp.utils.Utils;
 
 /**
- * Generates navigation HTML page where topic is not present in the table
- * of contents for the selected toc passed as request path info. Displays
- * links to the direct child topics.
+ * Generates either xml, json or html page having navigation informations where topic 
+ * is not present in the table of contents for the selected toc passed as request 
+ * path info. Displays links to the direct child topics.
  * 
  * <p>This servlet is called on infocenters by client workbenches
  * configured for remote help in order to generate the navigation pages.
@@ -34,13 +44,18 @@ import org.eclipse.help.internal.webapp.utils.Utils;
  * <p>Passes the request to {@link org.eclipse.help.internal.webapp.servlet.NavServlet}
  * servlet.
  *  
- * @return	An html page having the links to the direct child topics for
- * 			the selected toc
+ * @param returnType	- (Optional) specifies the return type of the servlet.
+ * 						  Accepts either <code>xml</code> (default) or <code>html</code>
+ * 						  or <code>json</code>
+ * 
+ * @return	A navigation information having the links to the direct child topics for
+ * 			the selected toc, either as <code>xml</code> (default) or
+ * 			<code>html</code> or <code>json</code>
  * 
  * @version	$Version$
  * 
  **/
-public class NavService extends HttpServlet {
+public class NavService extends NavServlet {
 
 	private static final long serialVersionUID = 1L;
 
@@ -48,6 +63,39 @@ public class NavService extends HttpServlet {
 			throws ServletException, IOException {
 		
 		req.setCharacterEncoding("UTF-8"); //$NON-NLS-1$
+		
+		String returnType = req.getParameter(Utils.RETURN_TYPE);
+		boolean boolIsHTML = (returnType != null 
+				&& returnType.equalsIgnoreCase(Utils.HTML));
+		// If HTML output is required, call AboutServlet class
+		if (boolIsHTML) {
+			processHTMLOutputRequest(req, resp);
+			return;
+		}
+		
+		// Set standard HTTP/1.1 no-cache headers.
+		resp.setHeader("Cache-Control",  //$NON-NLS-1$
+				"no-store, no-cache, must-revalidate"); //$NON-NLS-1$
+		resp.setContentType("application/xml; charset=UTF-8"); //$NON-NLS-1$
+		
+		// create XML response
+		String response = processRequest(req, resp);
+		
+		boolean boolIsJSON = (returnType != null 
+				&& returnType.equalsIgnoreCase(Utils.JSON));
+		
+		// If JSON output is required
+		if (boolIsJSON) {
+			resp.setContentType("text/plain"); //$NON-NLS-1$
+			response = getJSONResponse(response);
+		}
+		
+		resp.getWriter().write(response);
+	}
+	
+	private void processHTMLOutputRequest(HttpServletRequest req, HttpServletResponse resp)
+			throws ServletException, IOException {
+		
 		resp.setContentType("text/html; charset=UTF-8"); //$NON-NLS-1$
 		
 		String baseURL = req.getRequestURL().toString();
@@ -65,4 +113,72 @@ public class NavService extends HttpServlet {
 		writer.close();
 	}
 
+	protected String getJSONResponse(String response)
+			throws IOException {
+		NavParser navParser = new NavParser();
+		InputStream is = null;
+		try {
+			if (response != null) {
+				is = new ByteArrayInputStream(response.getBytes("UTF-8")); //$NON-NLS-1$
+				navParser.parse(is);
+			}
+
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		
+		if (is != null)
+			is.close();
+
+		// Call after the catch.
+		// An empty JSON is created if any Exception is thrown
+		// Else returns the complete JSON
+		return navParser.toJSON();
+	}
+
+	private String processRequest(HttpServletRequest req, HttpServletResponse resp)
+			throws ServletException, IOException {
+		Locale locale = getLocale(req, resp);
+		
+		String path = req.getPathInfo().substring(1);
+		int index = path.indexOf("service/nav/"); //$NON-NLS-1$
+		if (index > -1)
+			path = path.substring(index+12);
+		ITopic topic = getTopic(path, locale);
+		
+		AbstractHelpScope scope = RequestScope.getScope(req, resp, false);
+		return "" + writeContent(topic, path, locale, scope); //$NON-NLS-1$
+	}
+
+	private String writeContent(ITopic topic, String path, Locale locale,
+			AbstractHelpScope scope) {
+		StringBuffer buff = new StringBuffer();
+		buff.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"); //$NON-NLS-1$
+		
+		buff.append("<nav\n      title=\""); //$NON-NLS-1$
+		buff.append(XMLGenerator.xmlEscape(topic.getLabel()));
+		buff.append("\">"); //$NON-NLS-1$
+		
+		ITopic[] subtopics = topic.getSubtopics();
+		for (int i=0;i<subtopics.length;++i) {
+			if (ScopeUtils.showInTree(subtopics[i], scope)) {
+				buff.append("\n        <topic\n          href=\""); //$NON-NLS-1$
+				String href = subtopics[i].getHref();
+				if (href == null) {
+					href = path + '_' + i;
+				}
+				else {
+					href = XMLGenerator.xmlEscape(UrlUtil.getHelpURL(href));
+				}
+				buff.append(href);
+				buff.append("\"\n          title=\""); //$NON-NLS-1$
+				buff.append(XMLGenerator.xmlEscape(subtopics[i].getLabel()));
+				buff.append("\">\n        </topic>"); //$NON-NLS-1$
+			}
+		}
+		buff.append("\n</nav>"); //$NON-NLS-1$
+		
+		return buff.toString();
+	}
+
 }
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/AboutServlet.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/AboutServlet.java
index 2d2ae2073..40dc78956 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/AboutServlet.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/AboutServlet.java
@@ -35,12 +35,14 @@ import com.ibm.icu.text.Collator;
 
 public class AboutServlet extends HttpServlet {
 
-	private static final int NUMBER_OF_COLUMNS = 4;
+	protected static final int NUMBER_OF_COLUMNS = 4;
 	
-	private class PluginDetails {
-		private String[] columns = new String[4];
+	protected Locale locale;
+	
+	protected class PluginDetails {
+		public String[] columns = new String[NUMBER_OF_COLUMNS];
 		
-		PluginDetails(String[] columns) {
+		public PluginDetails(String[] columns) {
 			this.columns = columns;
 			for (int i = 0 ; i < NUMBER_OF_COLUMNS; i++) {
 				if (columns[i] == null) {
@@ -50,7 +52,7 @@ public class AboutServlet extends HttpServlet {
 		}
 	}
 	
-	private class PluginComparator implements Comparator {
+	protected class PluginComparator implements Comparator {
 		
         public PluginComparator(int column) {
         	this.column = column;
@@ -80,7 +82,7 @@ public class AboutServlet extends HttpServlet {
 			throws ServletException, IOException {
 		req.setCharacterEncoding("UTF-8"); //$NON-NLS-1$
 		resp.setContentType("text/html; charset=UTF-8"); //$NON-NLS-1$
-		Locale locale = req.getLocale();
+		locale = UrlUtil.getLocaleObj(req, resp);
 		StringBuffer buf = new StringBuffer();
 		buf.append(XHTML_1);
 		String showParam = req.getParameter("show"); //$NON-NLS-1$
@@ -89,7 +91,7 @@ public class AboutServlet extends HttpServlet {
 			return;
 		}
 		if ("preferences".equalsIgnoreCase(showParam)) { //$NON-NLS-1$
-			getPreferences(req, resp);
+			getPreferences(resp);
 			return;
 		}
 		String sortParam = req.getParameter("sortColumn"); //$NON-NLS-1$
@@ -132,16 +134,16 @@ public class AboutServlet extends HttpServlet {
 		resp.getWriter().write(response);		
 	}
 
-	private void getPreferences(HttpServletRequest req, HttpServletResponse resp) throws IOException {
+	private void getPreferences(HttpServletResponse resp) throws IOException {
 		StringBuffer buf = new StringBuffer();
 		buf.append(XHTML_1);
-		String title = WebappResources.getString("preferences", req.getLocale()); //$NON-NLS-1$
+		String title = WebappResources.getString("preferences", locale); //$NON-NLS-1$
 		buf.append(UrlUtil.htmlEncode(title));
 		buf.append(XHTML_2);
 		buf.append("<h1>"); //$NON-NLS-1$
 		buf.append(title);
 		buf.append("</h1>"); //$NON-NLS-1$
-		PreferenceWriter writer = new PreferenceWriter(buf, req.getLocale());
+		PreferenceWriter writer = new PreferenceWriter(buf, locale);
 		writer.writePreferences();
 		buf.append(XHTML_3);
 		String response = buf.toString();
@@ -151,7 +153,7 @@ public class AboutServlet extends HttpServlet {
 	private void getAgent(HttpServletRequest req, HttpServletResponse resp) throws IOException {
 		StringBuffer buf = new StringBuffer();
 		buf.append(XHTML_1);
-		String title = WebappResources.getString("userAgent", req.getLocale()); //$NON-NLS-1$
+		String title = WebappResources.getString("userAgent", locale); //$NON-NLS-1$
 		buf.append(UrlUtil.htmlEncode(title));
 		buf.append(XHTML_2);
 		buf.append("<h1>"); //$NON-NLS-1$
@@ -166,7 +168,7 @@ public class AboutServlet extends HttpServlet {
 
 	private String headerRowFor(PluginDetails details) {
 		String row = "<tr>\n"; //$NON-NLS-1$
-		for (int i = 0; i < 4; i++) {
+		for (int i = 0; i < NUMBER_OF_COLUMNS; i++) {
 			row += ("<td><a href = \"about.html?sortColumn="); //$NON-NLS-1$
 			row += i;
 			row += "\">"; //$NON-NLS-1$
@@ -179,7 +181,7 @@ public class AboutServlet extends HttpServlet {
 	
 	private String tableRowFor(PluginDetails details) {
 		String row = "<tr>\n"; //$NON-NLS-1$
-		for (int i = 0; i < 4; i++) {
+		for (int i = 0; i < NUMBER_OF_COLUMNS; i++) {
 			row += ("<td>"); //$NON-NLS-1$
 			row += UrlUtil.htmlEncode(details.columns[i]);
 			row += "</td>\n"; //$NON-NLS-1$
@@ -188,7 +190,7 @@ public class AboutServlet extends HttpServlet {
 		return row;
 	}
 
-	private Object pluginDetails(Bundle bundle) {
+	protected Object pluginDetails(Bundle bundle) {
 		String[] values = new String[] {
 		    getResourceString(bundle, Constants.BUNDLE_VENDOR),
 	        getResourceString(bundle, Constants.BUNDLE_NAME),
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/NavServlet.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/NavServlet.java
index fc3d1cc9c..b45853898 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/NavServlet.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/NavServlet.java
@@ -68,7 +68,7 @@ public class NavServlet extends HttpServlet {
 		writer.close();
 	}
 	
-	private Locale getLocale (HttpServletRequest req, HttpServletResponse resp) {
+	protected Locale getLocale (HttpServletRequest req, HttpServletResponse resp) {
 		Locale locale;
 		String nl = UrlUtil.getLocale(req, resp);
 		// break the string into tokens to get the Locale object
@@ -85,7 +85,7 @@ public class NavServlet extends HttpServlet {
 		return locale;
 	}
 	
-	private ITopic getTopic(String topicPath, Locale locale) {
+	protected ITopic getTopic(String topicPath, Locale locale) {
 		StringTokenizer tok = new StringTokenizer(topicPath, "_"); //$NON-NLS-1$
 		int index = Integer.parseInt(tok.nextToken());
 		ITopic topic = HelpPlugin.getTocManager().getTocs(locale.toString())[index].getTopic(null);
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/PreferenceWriter.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/PreferenceWriter.java
index 0cf320713..cfa9003bf 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/PreferenceWriter.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/servlet/PreferenceWriter.java
@@ -31,10 +31,16 @@ import org.osgi.service.prefs.BackingStoreException;
 public class PreferenceWriter {	
 	private StringBuffer buf;
 	private Locale locale;
+	private boolean isXML;
 	
 	public PreferenceWriter(StringBuffer buf, Locale locale) {
+		this(buf, locale, false);
+	}
+	
+	public PreferenceWriter(StringBuffer buf, Locale locale, boolean isXML) {
 		this.buf = buf;
 		this.locale = locale;
+		this.isXML = isXML;
 	}
 	
 	public void writePreferences() {
@@ -54,22 +60,43 @@ public class PreferenceWriter {
 			String[] allKeys = (String[]) keySet.toArray(new String[keySet.size()]);
 			if (allKeys.length > 0) {
 			    Arrays.sort(allKeys);
-			    buf.append("<h3>"); //$NON-NLS-1$
-			    buf.append(plugin);
-			    buf.append("</h3>"); //$NON-NLS-1$
-			    buf.append("<table>");  //$NON-NLS-1$
+			    
+			    if (!isXML) {
+			    	buf.append("\n<h3>"); //$NON-NLS-1$
+			    	buf.append(plugin);
+			    	buf.append("</h3>\n"); //$NON-NLS-1$
+			    	buf.append("<table>");  //$NON-NLS-1$
+			    } else {
+					buf.append("\n    <plugin\n          title=\""); //$NON-NLS-1$
+					buf.append(XMLGenerator.xmlEscape(plugin));
+					buf.append("\">"); //$NON-NLS-1$
+			    }
 			    for (int i = 0; i < allKeys.length; i++) {
-			    	buf.append("<tr>"); //$NON-NLS-1$
 			    	String key = allKeys[i];
-			    	buf.append("<td>"); //$NON-NLS-1$
-			    	buf.append(UrlUtil.htmlEncode(key));
-			    	buf.append("</td><td>"); //$NON-NLS-1$
 			    	String value = Platform.getPreferencesService().getString
 			    			(plugin, key, "", null); //$NON-NLS-1$
-					buf.append(UrlUtil.htmlEncode(value)); 
-					buf.append("</td></tr>"); //$NON-NLS-1$
+			    	if (!isXML) {
+				    	buf.append("\n    <tr>\n"); //$NON-NLS-1$
+				    	buf.append("        <td>"); //$NON-NLS-1$
+				    	buf.append(UrlUtil.htmlEncode(key));
+				    	buf.append("</td>\n        <td>"); //$NON-NLS-1$
+						buf.append(UrlUtil.htmlEncode(value));
+						buf.append("</td>\n    </tr>"); //$NON-NLS-1$
+			    	} else {
+				    	buf.append("\n        <"); //$NON-NLS-1$
+			    		buf.append(key);
+			    		buf.append(">"); //$NON-NLS-1$
+						buf.append(value);
+				    	buf.append("</"); //$NON-NLS-1$
+			    		buf.append(key);
+			    		buf.append(">"); //$NON-NLS-1$
+			    	}
+			    }
+			    if (!isXML) {
+			    	buf.append("\n</table>"); //$NON-NLS-1$
+			    } else {
+			    	buf.append("\n    </plugin>"); //$NON-NLS-1$
 			    }
-			    buf.append("</table>"); //$NON-NLS-1$
 			}
 		} catch (BackingStoreException e) {
 			buf.append(WebappResources.getString("badPreferences", locale)); //$NON-NLS-1$
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/JSonHelper.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/JSonHelper.java
index a59ff8bc9..fd829c450 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/JSonHelper.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/JSonHelper.java
@@ -32,6 +32,7 @@ public final class JSonHelper {
 	public static final String NAME				= "name"; //$NON-NLS-1$
 	public static final String TITLE			= "title"; //$NON-NLS-1$
 	public static final String ID				= "id"; //$NON-NLS-1$
+	public static final String PLUGIN_ID		= "pluginId"; //$NON-NLS-1$
 	public static final String HREF				= "href"; //$NON-NLS-1$
 	public static final String TYPE				= "type"; //$NON-NLS-1$
 	public static final String CHECKED			= "checked"; //$NON-NLS-1$
@@ -45,7 +46,8 @@ public final class JSonHelper {
 	public static final String CATEGORY			= "category"; //$NON-NLS-1$
 	public static final String DESCRIPTION		= "description"; //$NON-NLS-1$
 	public static final String CATEGORY_HREF	= CATEGORY+"_"+HREF; //$NON-NLS-1$
-	public static final String PROPERTY_NAME	= "propertyName"; //$NON-NLS-1$
+	public static final String PROPERTY_NAME	= "tagName"; //$NON-NLS-1$
+	public static final String PROPERTY_VALUE	= "value"; //$NON-NLS-1$
 	public static final String INDEX			= "Index"; //$NON-NLS-1$
 	public static final String TOPIC			= "Topic"; //$NON-NLS-1$
 	public static final String NUMERIC_PATH		= "NumericPath"; //$NON-NLS-1$
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/Utils.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/Utils.java
index f07d767ed..01ccc51ef 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/Utils.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/Utils.java
@@ -30,6 +30,12 @@ public class Utils {
 	// returnType values: xml (default) | json
 	public static final String XML 					= "xml"; //$NON-NLS-1$
 	public static final String JSON 				= "json"; //$NON-NLS-1$
+	public static final String HTML 				= "html"; //$NON-NLS-1$
+	
+	// Constants for About service
+	public static final long AGENT			= 1L;
+	public static final long PREFERENCE		= 2L;
+	public static final long ABOUT_PLUGIN	= 3L;
 	
 	public static String convertStreamToString(InputStream is)
 			throws IOException {
diff --git a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/XMLHelper.java b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/XMLHelper.java
index b8513a400..d50eb498d 100644
--- a/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/XMLHelper.java
+++ b/org.eclipse.help.webapp/src/org/eclipse/help/internal/webapp/utils/XMLHelper.java
@@ -34,6 +34,9 @@ public final class XMLHelper {
 	public static final String ELEMENT_SUMMARY			= "summary"; //$NON-NLS-1$
 	public static final String ELEMENT_DESCRIPTION		= "description"; //$NON-NLS-1$
 	public static final String ELEMENT_INDEX			= "index"; //$NON-NLS-1$
+	public static final String ELEMENT_PREFERENCES		= "preferences"; //$NON-NLS-1$
+	public static final String ELEMENT_PLUGIN			= "plugin"; //$NON-NLS-1$
+	public static final String ELEMENT_ABOUT_PLUGINS		= "aboutPlugins"; //$NON-NLS-1$
 	public static final String ELEMENT_INDEX_CONTRIBUTIONS	= "indexContributions"; //$NON-NLS-1$
 	public static final String ELEMENT_TOC_CONTRIBUTIONS	= "tocContributions"; //$NON-NLS-1$
 	public static final String ELEMENT_NUMERIC_PATH			= "numeric_path"; //$NON-NLS-1$